Thailand’s islands are some of the most visited places on planet tourism, but you can still go wrong. Time Out’s resident Thailand addict Derek Adams gives us his informed guide to what to see, where to stay and what to avoid.

Thailand hasn’t enjoyed the greatest of press recently, what with the demonstrations in 2010, the fear of tsunamis and the fact that some parts of the island have been over developed into a touristic paean to self-indulgence, sex and general hedonism. While we can’t vouch for further ‘red shirt’ demos or the (rare) recurrence of big waves, we want to point readers in the direction of the very best this beautiful and deservedly popular country has to offer. Rather than tease you with a report from a balmy beach somewhere, the following is a user’s guide to some of the Andaman Sea and Gulf of Thailand’s most exquisite islands, along with practical information and a selection of the best places to stay. Better get booking, then.

Andaman Sea

Phuket

For some reason – ignorance, probably – the whole of Phuket island has become associated with its most popular tourist destinations: the beach areas of Patong, Kata and Karon. This trio of towns is the equivalent of three Newquays in a row. Despite the geographical beauty surrounding it, Patong, especially, has become a place to avoid like the plague: it’s basically a conglomeration of chain hotels, cheap digs and sex-themed bars and clubs. Not somewhere to take the kids, then. But the reasons most travellers opt for Phuket are that a) it has some of the world’s finest hotels and b) it makes an excellent base from which to explore the surrounding islands and their beaches. Phuket also has some excellent beaches of its own, and the southern tip at Rawai is one of the best areas to grab a longtail boat for a trip to the nearest islands.

Where to stay

Evason Phuket & Six Senses Spa, RawaiThis hilly coastal hotel complex has rustic chic written all over it. Comfort is supreme throughout, whether you’re lounging beside one of the three pools, chilling in the reception area or collapsing on to your marshmallow-soft bed. The Evason also offers guests free access to its own private island, Koh Bon, just a few kilometres away. From here you can take out a Hobycat or simply drift with the current along its amazing coral reef. Rooms from £69 per night (www.sixsenses.com/evason-phuket).

Vijitt Resort, RawaiThis large, immaculately kept African-style resort’s pièce de résistance is its 40-metre infinity pool which affords beautiful palm-framed views across Chalong Bay. Breakfast is expansive, the staff are friendly and all villas are equipped with free internet access. Because the sea comes in on a long, shallow sandbank, it’s not really possible to swim here. But there are shuttles to and from nearby Nai Harn beach. One for tranquillity seekers. Rooms from £77 (www.vijittresort.com).

Beyond Phuket

If years of unchecked development have spoiled parts of Phuket, remember that this slice of west coast is only a teeny weeny fraction of what lies beyond. Phuket is just one of 39 main islands and a hundred or so smaller ones dotted about the region. If you’re prepared to stretch your horizons, you’ll unearth a raft of settings with such unspoilt natural beauty you really will begin to wonder what all the criticism was about.

Koh Hae (Coral Island)

As the English moniker indicates, this popular day-trip island has its own reef just off the beach. Because it’s the easiest island to reach from south Phuket, don’t expect to be the only visitor.

Koh Lanta

Just off Thailand’s south-western town of Krabi lies the spacious island of Koh Lanta with its verdant undergrowth and 27-kilometre coastline. To really explore, hire a moped and head southwest to the Mu Ko Lanta National Park with its great snorkelling and abundance of wildlife. Or take a boat 30 kilometres to the tiny uninhabited islands of Koh Rok Nok and Rok Nai. The snorkelling here is sublime, with regular sightings of blacktip reef sharks and hawksbill turtles.

Koh Mook, Koh Ngai and Koh Radang

This small chain of islands south-east of Phi Phi sports a set of rocky limestone outcrops similar to those at Phang Nga. Koh Mook is especially worth a detour for its Morakot Cave. When the centre of this hong collapsed, it created an aquamarine basin surrounded by a semi-circular beach amid near-vertical cliffs. It’s like something out of ‘The Land That Time Forgot’, but the only way to see it is by swimming through a 70-metre tunnel under the cliff face!

Koh Phi Phi

What needs to be said about Phi Phi that isn’t already known? Despite the crowds, Maya Bay – where ‘The Beach’ was shot – is as stunning a vista as ever but there are plenty of other coves within easy reach. Take a dip at Pileh Lagoon, nature’s grandest swimming pool, visit Monkey Island and its macaques and snorkel in waters so clear you can see further than 50 metres.

Koh Racha

Nineteen kilometres off the south coast of Phuket lies a beautiful island few bother to visit. Koh Racha is surrounded by crystal-clear waters and has two gorgeous Dulux-white beaches to boast about. At Siam Bay we found paradise in the shape of a rustic bamboo beach restaurant that served the best banana curry we’ve ever tasted.

Koh Yao Yai and Koh Yao Noi

Situated off the east coast of Phuket, these islands are home to some very high-end resorts. Otherwise they’re relatively untouched by tourism. This is exactly what Phuket looked like in the ’80s, dirt roads and all.

Krabi

Although on the mainland, Krabi deserves special mention for its spotless beaches. Some are so soft that the sand puffs up like talcum powder when you walk on it.

Railay Beach is the area’s most famous hangout, a promontory with a beach on either side; West Railay is the posher side and East Railay the backpackers’ side. Krabi also offers access to places like Chicken Island (with its chicken-shaped rock) and the Phi Phi islands.

Phang Nga

Phang Nga Bay is a remarkable sanctuary of some 60 towering limestone outcrops, some of which have collapsed in the centre to form hongs (huge hollowed rooms with sunlight above) that are usually accessible at low tide. The water around here is emerald green and the whole area is simply breathtaking, even if the scene sometimes resembes a regatta.

Most tours will include a visit to the very touristy floating Muslim village of Koh Panyi.

Where to stay

Koh Rok Nok campingEasily reached from Koh Lanta, the alluring, uninhabited island of Koh Rok Nok has a small camping ground at Had Koh Rok. With its powder beach, offshore coral reef and virgin waters, this offers the real Robinson Crusoe experience. You can hire a four-person tent for around £7 per night, with electricity provided between 6pm and 8pm.

Don’t forget to take food, drinking water and mosquito protection because there are no shops. Make reservations at the National Park HQ in the south of Koh Lanta.

Railei Beach ClubEstablished in 1985 as a sort of hippy hangout, this hamlet offers a selection of traditional Thai properties for rent among lush vegetation within metres of the exceptional West Railay beach. Some of these houses are built on stilts, their top floors poking out of the surrounding jungle canopy – with monkeys swinging in the trees.

It’s a lovely area and highly recommended. Prices are reasonable too, especially if you’re with a few friends. Rooms from £25 (www.raileibeachclub.com).

Sri Lanta

Located at the quieter end of Koh Lanta, this lovely, well-appointed resort offers a selection of contemporary stilted villas with mountain and garden views. It’s a superb location with a fabulous pool and access to the beach from which to observe the amazing sunsets. Rooms from £62 (www.srilanta.com).

Gulf of Thailand

Koh Phangan

Haad Rin’s crescent beach is famous for its alcohol-fuelled Full Moon parties and best avoided unless you like loud music and a bit of debauchery. One of the first drinks you’re offered on arrival is a concoction of rum, Coke and Red Bull syrup all mixed up in a bucket. One hit of that and you’ll be rat-arsed for the rest of the night only to wake up without your belongings – or your pride. By contrast, the island at any other times is well worth putting on your itinerary.

Koh Samui

Despite its ever-increasing popularity, palm-wafted Koh Samui provides a vibrant island experience. Most tourists continue to flock to the crescent-shaped beach at Chaweng on the east coast but unless you like loud reggae and blues, we’d suggest avoiding the clamour and clutter and heading instead to its more tranquil southern tip at Chaweng Noi. If you get a chance, take time out to see the impressive Big Buddha complex en route to the charming wooden village of Bophut on the north coast. From here you can also board a speedboat or ferry to Koh Phangan and Koh Tao. Finally, don’t miss a day trip to Angthong National Marine Park. This is the Thailand you see on postcards – wicked limestone mountain islands in turquoise water.

Koh Tao and Koh Nangyuan

The sea around Koh Tao provides some of the best diving in the Gulf of Thailand (hence the island’s many diving clubs), but it’s the nearby tiny twin islands of Koh Nangyuan that impresses most. A sand bar dividing the islands at low tide gives this setting true paradise status. Just a shame that it’s so popular and that getting there is such a schlep. Not much to do here either, except chill and snorkel off the gorgeous beach.

Where to stay

Impiana Resort, Chaweng NoiThe best thing about this modern mid-range hotel is that it has direct access to Chaweng Noi beach. Its beach bar is worth a special mention for its superb pad thai and head-spinning cocktails. Rooms from £50 (www.impiana.com).

Palita Lodge, Koh PhanganSituated on Haad Rin Beach, the huts here have a contemporary feel and great stone designer bathrooms. Not bad for around £38 a night. Grab some hot fresh popcorn and wash it down with a Chang beer while swinging in your hammock. Rooms from £38 (www.palitalodge.com).

The Sarann, Chaweng NoiThis swish boutique resort comprises around 40 Japanese-style villas and an infinity pool overlooking the crescent-shaped beach below. The seafront pool villas are the best choice since they have the finest views. The resort is quite shaded, but there’s plenty of sunshine by the main pool and down on the beach. A tour of the island can be arranged for less than it would cost to hire a taxi. If you’re looking for five-star luxury with views to match, The Sarann suffices in all respects. Rooms from £117 (www.thesarann.com).

Tapan Noi, Kho PhanganThis basic but charming retreat has beachfront bungalows built on the rocks at the far end of Thong Nai Pan Noi beach. Some would say they’re falling into disrepair, but at just £6 a night, who’s complaining? The adjoining restaurant has seating on the beach and serves up brilliant barbecues, including crocodile meat. Rooms from £6 (www.thongnaipan.info/tapannoi.html).

Fast facts

Safety

The situation in Thailand has calmed down greatly since the protests in May. The Thai government recommends tourists stay away from Red Shirt and protest areas. If you think you spot trouble, stay in your hotel and wait for the situation to calm down. If you aren’t convinced about staying in Bangkok, just go straight on to the beach.

Getting there

Direct flights: Thai Airways flies twice daily to Bangkok; EVA Airways flies daily, and has a code share with Bangkok Airways to sell through fares to Chiang Mai, Phuket and Samui; BA and Qantas both fly daily. Indirect flights: many, through the Gulf, Hong Kong, Europe and Singapore. Compare prices before booking – returns to Bangkok via the Gulf start at around £340. Budget travellers can opt for low-cost airline Air Asia, which flies from Stansted to Bangkok via Kuala Lumpur.

Boat hire

The best way to enjoy the Andaman Sea region is by chartered boat. The beauty of having your own boat is that you get to sample some of the most popular settings when all the tour boats have gone. You can choose where you want to go and when, and enjoy the freedom of anchoring up for the night in some heavenly cove with no one else around you. Siam Sailing – which we’ve used on three occasions – provides large, stable, eight-berth catamarans with skipper (or without if you’re an experienced sailor) from its base at Chalong, Phuket. Minimum hire is three days.

Ultimate boat trip

Most longtail boats will take you to any of the nearby islands but if you want to visit further afield you’ll need to book a tour. We took a gamble on Simba Sea Trips and hit the jackpot. Simba offers trips to Phi Phi, Phang Nga and Krabi. The savvy Simba crew get you to the main spots before all the other crammed-to-the-gills tour boats arrive. It may cost more than other tours (around £60) but it’s worth it.

Weather

The islands enjoy a humid, tropical climate influenced by three seasons: hot, dry and rainy. The best time to visit is the dry (and peak) season between mid-November and March when there’s hardly any rain, it’s less humid, not quite as stiflingly hot (around 28C) and the sea is calm and clear. Other times of year are worth considering; bear in mind that May is usually the wettest. During the monsoon periods the sea can be silty (not great for snorkelling) and boat trips may be cancelled due to swells.

Snorkelling

Many holidaymakers come to the Phuket region for the snorkelling. And small wonder – it’s like swimming in an aquarium. Little sergeant majors are in abundance from the moment you wade in. For the full Cousteau effect, head out to one of the coral reefs, some of which are easily accessed via a short 20-metre swim from the beach. Take along a banana and before long you’ll be engulfed in shoals of vibrantly coloured fish. There are rarely any sea nasties to worry about. Most diving centres hire out masks and snorkels, though we’d advise taking along your own.

The Andaman Sea is a world-class diving site, and the cheapest area in the world to gain a PADI licence. There are numerous dive centres from which to arrange a local trip and they all supply equipment. The best deep-water diving areas are around Phi Phi, the Similan Islands (84km north-west of Phuket) and the Surin Islands on the borders of Burma. Koh Tao in the Gulf of Thailand is also popular.

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